The present disclosure relates to seal assemblies. More particularly, the present disclosure relates to intershaft seal assemblies in aircraft engines.
In aircraft engines, intershaft sealing is difficult for many reasons such as space limitations, unique deflections of the shafts, and counter-rotating surfaces of the shafts. Additionally, machining of sealing features into high cost parts is risky. During operation of the aircraft engine, contact points of an intershaft sealing assembly that are prone to rubbing can cause thermal mechanical fatigue issues. Additionally, maneuvers can make it difficult to maintain necessary gaps between the seal assembly and rotating shafts. Traditional labyrinth or knife edge seals are typically employed to maintain necessary transient thermals tolerances.